The present invention relates to a method of handwriting recognition.
Studies carried out for many years on the recognition of handwriting by the machine have shown that many problems were raised. The following paragraphs will briefly state these problems and how they may be solved.
The basic elements of writing are the letters and the numerals (let alone specialized signs) and they will be called "writing elements" in the following. These elements are gathered or arranged into words but their recognition should begin with their individualizations. In the printed writing, the letters and other signs are separated (characters) and their boundaries therefore raise no problems. On the contrary, in connected handwriting the elements of the tracing which are representative of writing elements are not individualized (this is the case of the letters in general since the numerals are usually separated from each other) and their recognition therefore requires their boundaries to be previously marked off or the characters to be previously cut out.
Once the tracing has been cut into elements, it is necessary to identify each one of these elements by determining the writing element to which it corresponds. This identification relies upon the use of very various criterions such as sizes, curvatures, slopes, directions etc.
A first approach has been the search for the criterions allowing the "absolute" identification of the writing elements, i.e. which would hold true for any handwritings whatsoever. This approach is successful only if the person who is writing would accept to comply with a very strict presentation, with well shaped letters of regular size and constant orientation.
It has therefore been tried to avoid such constraints by the use of an apprenticeship phase or learning step. In such a case, in a phase previous to the recognition, the person who is writing would trace a known text and the characterizing features of each letter (obtained by applying successive various criterions) would be retained and used later for the comparison with other characterizing features. This process actually makes possible the recognition of handwriting. It however requires a great number of elementary operating steps for being practiced since all the criterions are applied to every tracing element and would give rise to a comparison.
The present methods therefore do not allow the real time recognition of practically any handwritings whatsoever by making use of devices of reasonable powers such for instance as microcomputers.